Trailer lock



FIG. 1 is a perspective view of a trailer lock embodying my design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a side elevational view taken from the left of FIG. 1;

FIG. 5 is a side elevational view taken from the right of FIG. 1. 

The ornamental design for a trailer lock, as shown and described. 